Cable television (CATV) networks supply and distribute high frequency “downstream” signals from a main signal distribution facility, known as a “headend,” to premises (e.g., homes and offices) of subscribers. The downstream signals can be provided to subscriber equipment, such as televisions, telephones, and computers. In addition, most CATV networks also receive and transmit “upstream” signals from subscriber equipment back to the headend of the CATV network. For example, set top boxes can send upstream signals including information for selecting programs for viewing on a television. Also, upstream and downstream signals are used by personal computers via modems connected through the CATV infrastructure to the Internet. Further, voice over Internet protocol (VOIP) telephones use upstream and downstream signals to communicate telephone conversations.
To permit simultaneous communication of upstream and downstream CATV signals, and to permit interoperability of the subscriber equipment and the equipment associated with the CATV network infrastructure outside of subscriber premises, the downstream and upstream signals are confined to two different frequency bands. For example, in some CATV networks, the downstream frequency band can be within the range of 54-1002 megahertz (MHz), and the upstream frequency band can be within the range of 5-42 MHz.
The upstream frequency band may be susceptible to ingress noise from a variety of sources, both within and exterior to the subscriber's premises. The noise may have little effect on an individual subscriber's experience using the network, but can burden the network on the plant-level. When the source of the noise is exterior to the premises, the source can be addressed by routine maintenance. However, when the source of the noise is within a subscriber's premises, which is common, the subscriber's consent is needed for the appropriate remedial measures to be taken. This can be a challenge, because the subscriber may not recognize that the noise is burdening the plant, and thus may have little or no incentive to provide access to the provider.